Question

Graph of the quadratic function f(x)=‒(x+4)(x‒6) is shown on the coordinate grid below.

Which statement is not true?
A.
The maximum of this function occurs when y=25.
B.
The function increases in the interval 1 to 6.
C.
The has a zero at (‒4,0).
D.
The function positive in the interval ‒4 to 6.

Answer 1

the correct answer is c because zero wasnt incluing and it said positive 4 to -6

Answer 2

Option B is not true.

Explanation:

The quadratic function is f(x) = -(x + 4)(x - 6)

Now we check each option given

Option A.

It is clear from the graph function is maximum at y = 25.

TRUE.

Option B.

Function increases in the interval 1 to 6.

Let's check this at x = 2 and x = 3

f(2) = -(2 + 4)(2 - 6)

= -(6)(-4)

= 24

f(3) = -(3 + 4)(3 - 6)

= - (7)(-3)

= 21

So we find this function is decreasing in this interval.

So the given option is FALSE.

Option C.

The function has a zero at (-4, 0)

f(-4) = -(-4 + 4)(-4 + 6) = 0

So the function has a zero at (-4, 0).

Option is True.

Option D.

The function is positive in the interval -4 to 6

f(x) = -(x + 4)(x - 6)

f(-3) = -(-3 + 4)(-3 - 6)

= -(1)(-9)

= 9

f(0) = -(0 + 4)( 0 - 6)

= 24

Therefore, this function is positive in this interval so the option is TRUE.

Option B is not true.